Driver-assistance systems, which assist the driver in guiding the vehicle or which are also able to carry out driving maneuvers in a fully automated manner, are increasingly used in modern motor vehicles. One function of these systems consists of lane-change assistance. In such cases, the position of the vehicle in relation to an ascertained target lane is sensed and compared with a setpoint value. The output signal then consists of an actuating signal for an actuator that intervenes in the lateral guidance system of the vehicle, for instance in order to assist the driver through an additional steering torque, or in order to execute a fully autonomous lateral guidance that no longer requires an intervention on the part of the driver.
For example, a method for assisting the driver of a vehicle in a lane change is discussed in German patent document DE 43 13 568 C1. In this case, vehicles in the adjacent target lane are detected and their speeds and their distances from the own vehicle as well as safety distances are ascertained and employed as the basis for the decision as to whether a gap that is suitable for a lane change is available.
German patent document DE 100 12 737 B4 discusses a lane-change assistant, which offers assistance to the driver in the lateral guidance. To do so, a lateral position trajectory is ascertained as a function of positional and traffic lane information, and an intervention in the lateral vehicle guidance is undertaken in accordance with the ascertained lateral position trajectory.